January 5, 2023
– by Debbie Quinn –
We’ve all done it. You catch a cold, get a fever, or feel the symptoms of a stomach bug. My first thought is always “Where could I have gotten that?” I think back to the food I’ve eaten and the people I’ve been in close contact with – especially children. I’ve even called up restaurants to see if anyone else has gotten sick there recently. I can usually kind of put a finger on where or who I got it from. It makes me feel like a private detective trying to identify clues.
While I may not be a detective, what I was actually doing was an informal version of contact tracing.
Contact tracing is the process of identifying, assessing, and managing people who may have been around someone with an infectious disease. It’s the process of trying to find out “where did they catch that?” The process starts with “tracing” the contacts of infected individuals, testing them for infection, isolating or treating infected people, and then tracing their “contacts.”
The goal is to slow or stop the spread of infection. This includes alerting contacts to possible infections, offering support for individuals who are already infected with the disease, and preventing reinfection. Contact tracing also helps professionals learn about how the disease spreads in certain populations.
Contact-tracing is one of the greatest tools that countries should deploy and use effectively to contain the outbreak.Tolbert Nyenswah, former director of Liberia’s public-health institute
Contact tracing begins with informed, engaged and enabled communities. For contact tracing to be successful, communication with the public is crucial. Community leaders can foster public awareness, understanding and acceptance of contact tracing. This could start with churches and community centers leading the charge to give community members the information needed to take responsibility and follow the guidance from public health agencies.
Everyone can play a part in keeping infectious diseases like COVID-19, seasonal cases of flu, and RSV (respiratory infectious disease) under control. The World Health Organization offers guidance on what to do if you have been in contact with an infectious virus: agree to monitoring, report signs or symptoms promptly, and be prepared to quarantine or go into isolation if you have a confirmed case of any of these respiratory infections.
Disease control: A (very) brief history
Governments’ and hospitals’ responses to disease control began during the plague epidemic of 1347–1352. The plague was initially spread in Italy by sailors, rats, and cargo. It quickly spread throughout Italy and to other countries, wiping out the population. Quarantining individuals with the disease was the only way to stop it.
Contact tracing has been a pillar of contagious disease work in public health for decades. It’s a practice that can be traced to the 1920s and ‘30s when it was a staple in controlling the influenza of 1918 and syphilis.
A recent example was during the 2014-2016 Ebola epidemic. In West Africa, health workers controlled the disease by finding and quarantining contacts of those who caught the disease.
“Contact-tracing is one of the greatest tools that countries should deploy and use effectively to contain the outbreak,” said Tolbert Nyenswah, the former director of Liberia’s public-health institute and current infectious-diseases researcher at Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland.
Contact tracing and COVID-19
During the COVID-19 pandemic, contact tracing became a term we all became more familiar with. We heard it often on TV, online and from our doctors and nurses.
Identifying an infection source so that person can isolate is the only way to stop the spread of fast-moving infections. Diseases that are very contagious like COVID-19 can spread rapidly through families and neighborhoods. This places a strain on doctors’ offices, ERs, outpatient clinics, and hospitals, as well as people’s jobs and lives.
The conventional form of contact tracing is forward tracing, where one looks for contacts after infection to prevent further disease spread. But during the COVID-19 pandemic, countries like Japan and South Korea found success with the inclusion of backward contact tracing, or looking at contacts before infection to identify the source. When adding backward contact tracing to methods, studies have shown 2-3 times more cases are identified.
Across the Western world, countries have floundered with the most basic test-trace-isolate procedures. In England, tracers fail to get in touch with one in eight people who tested positive for COVID-19; 18% of those who were reached provided no details of close contacts. In some regions of the United States, more than half of people who tested positive provided no details of contacts when asked, tests were slow to come back and many individuals didn’t wear masks to protect themselves and others. In many cases, people who did find out they were positive did not or could not self-isolate, and contact tracers were not deployed widely or quickly enough to stem the flow of the virus.
Contact tracing: Learning the basics
Contact tracing is a specialized skill. To be done effectively, it requires people with the training, supervision, and access to social and medical support for patients and contacts. According to the CDC, knowledge and skills required for contact tracers include, but are not limited to:
- An understanding of patient confidentiality, especially while conducting interviews.
- Understanding of the medical terms and principles of exposure, infection, infectious period, potentially infectious interactions, symptoms of disease, pre-symptomatic and asymptomatic infection.
- The ability to build and maintain trust with patients and contacts with interpersonal and cultural sensitivity.
- Basic skills in crisis counseling, and the ability to confidently refer patients and contacts for further care if needed.
- Resourcefulness in locating patients and contacts who may be difficult to reach or reluctant to talk to health resource individuals.
- Understanding of when to refer individuals or situations to medical, social, or supervisory resources.
If you’re interested in becoming certified in contact tracing, Johns Hopkins University offers a free COVID-19 Contact Tracing course. In this introductory course, you’ll learn how to:
- Describe the natural history of SARS-CoV-2, including the infectious period, the presentation of COVID-19, and evidence for how it is transmitted.
- Define an infectious contact and timeline for public health intervention through contact tracing.
- Demonstrate the utility of case investigation and contact tracing, identify common barriers, and possible strategies to overcome them.
- Present some ethical considerations around contact tracing, isolation, and quarantine.
The full course should take about 7 hours to complete.
If you’re not looking to become certified but want to learn more about contact tracing, the Equitable Neighborhoods Initiative has developed a condensed version of the course. This 45-minute course is intended to give you a basic overview of contact tracing. The best part? You can learn from anywhere: so sit on your porch, your couch or at your kitchen table and give it a view. Reach out to firstname.lastname@example.org to access the abbreviated course.